sigwait(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | ATTRIBUTES | CONFORMING TO | NOTES | EXAMPLES | SEE ALSO | COLOPHON

SIGWAIT(3)              Linux Programmer's Manual             SIGWAIT(3)

NAME         top

       sigwait - wait for a signal

SYNOPSIS         top

       #include <signal.h>

       int sigwait(const sigset_t *restrict set, int *restrict sig);

   Feature Test Macro Requirements for glibc (see
   feature_test_macros(7)):

       sigwait():
           Since glibc 2.26:
               _POSIX_C_SOURCE >= 199506L
           Glibc 2.25 and earlier:
               _POSIX_C_SOURCE

DESCRIPTION         top

       The sigwait() function suspends execution of the calling thread
       until one of the signals specified in the signal set set becomes
       pending.  The function accepts the signal (removes it from the
       pending list of signals), and returns the signal number in sig.

       The operation of sigwait() is the same as sigwaitinfo(2), except
       that:

       * sigwait() returns only the signal number, rather than a
         siginfo_t structure describing the signal.

       * The return values of the two functions are different.

RETURN VALUE         top

       On success, sigwait() returns 0.  On error, it returns a positive
       error number (listed in ERRORS).

ERRORS         top

       EINVAL set contains an invalid signal number.

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).

       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │Interface                             Attribute     Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │sigwait()                             │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO         top

       POSIX.1-2001, POSIX.1-2008.

NOTES         top

       sigwait() is implemented using sigtimedwait(2).

       The glibc implementation of sigwait() silently ignores attempts
       to wait for the two real-time signals that are used internally by
       the NPTL threading implementation.  See nptl(7) for details.

EXAMPLES         top

       See pthread_sigmask(3).

SEE ALSO         top

       sigaction(2), signalfd(2), sigpending(2), sigsuspend(2),
       sigwaitinfo(2), sigsetops(3), signal(7)

COLOPHON         top

       This page is part of release 5.13 of the Linux man-pages project.
       A description of the project, information about reporting bugs,
       and the latest version of this page, can be found at
       https://www.kernel.org/doc/man-pages/.

Linux                          2021-03-22                     SIGWAIT(3)

Pages that refer to this page: kill(2)signalfd(2)sigsuspend(2)sigwaitinfo(2)pthread_sigmask(3)pthread_sigqueue(3)sigqueue(3)nptl(7)signal(7)